


Two-Legged Mussel Picker

by De_Nugis



Category: Supernatural
Genre: Angel True Forms, M/M, Trueform Sex
Language: English
Status: Completed
Published: 2015-09-27
Updated: 2015-09-27
Packaged: 2018-04-23 15:58:46
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,017
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/4882957
Author URL: https://archiveofourown.org/users/De_Nugis/pseuds/De_Nugis
Summary: <blockquote class="userstuff">
              <p>Sam and Cas try trueform sex. It's different.</p>
            </blockquote>





	Two-Legged Mussel Picker

**Author's Note:**

> 1\. written for spn_masquerade for the prompt: "Sam reads about angel true forms in the bunker library and gets curious about what Cas looks like outside his vessel. After a bit of affectionate nagging Cas acquiesces, and true form sex ensues. Get as weird and creative as you want with the true form, as long as they both enjoy the sex."
> 
> 2\. title from Sylvia Plath, "Mussel Hunter at Rock Harbor"
> 
> 3\. brief mentions of the following pairings and kinks: Sam/Jess, Sam/Amelia, cunnilingus, pain kink, blood kink

Cas is _big_. It’s hard to register anything else. It’s pressing on Sam everywhere, not like being held down or tied up, not like a weight or a grip, just a vast, looming pressure of presence. Sam feels like he’s under a mile of sentient water, still breathing. The moving shadows across the amorphous plain that surrounds them could be whales.

“Get up, boy.”

Cas’s voice sounds like itself in Sam’s head, even though there’s no sign of his Jimmy vessel. But it’s what Sam thinks of as his angel voice, the soldier’s crack of command. He clambers to his feet. His limbs feel heavy, but powerful. It’s hard to look around, though, hard to keep standing. Part of him wants to kneel, to fall on his face, to hide his eyes and revel in the spangled darkness behind his lids, in the rough press of ground against every inch of his body. He could prostrate himself and let Cas’s shadow crush him. His mouth goes dry at the thought. 

But another part of him is stubborn. He forces his gaze up, scanning the complex, vertical planes in front of him. Cas — Castiel — does look like a skyscraper, at least at some angles of the shifting not-light. Chrysler building, huh. But there’s something off. Sam shouldn’t be able to see as high as he can from where he’s standing. The off-the-scale scale is fucking with his brain. He doesn’t know what to do with this. No part of him knows what to do with this. 

He still wants to try, though. This doesn’t look anything like sex, but there’s a shaping pull, a need to get closer, that tells Sam it’s going work, that the experience will translate. Cas is a threat and a promise, and Sam’s dick hardens in response.

“Well?” says Cas. _You asked for this_ , the voice implies. Sam had. He’d been curious. And there’s a question he wants answered.

“This is your territory,” he counters. Cas isn’t making it easy for him. Sam can return the favor. “I mean, the _boy_ thing is kinky,” (and effective — Sam hopes his silent parenthesis isn’t an audible prayer, but he suspects Cas has known all along), “but I think the first move is on you.” Hand Cas the initiative, see how he copes with that.

The structure in front of Sam shrugs and shifts, becomes a mountain shaggy with forest, a glitter of snow in impossible perspective at its peak. Then the sun on the snow dazzles back to glass and built stone.

“Mobility is not among my attributes here,” says Cas. “If movement is what you want, you’ll have to provide it. You wanted a challenge.” Light shimmers on ice, on high windows. Cas is laughing at him, the bastard. And what the hell is Sam supposed to do? There’s the problem of scale, and there’s also a distinct absence of appendages.

This is Dean’s fault, Sam realizes. Sam does not, he absolutely does not, watch the porn Dean bookmarks on the laptop. Any glimpses he’s caught have been completely involuntary. They’ve made an impression, all the same. Dean is wholly responsible for the fact that somehow, in Sam’s (vital! strictly professional!) trueform research in the Bunker library, he’d come to expect, well, tentacles. Chrysler Building, sure, OK, he could work with that, but a Chrysler Building with tentacles. He’d had plans for tentacles.

It would be rude to reproach Cas with that, though. Also undignified and whiny. But blaming Dean at least gives Sam a comfortable foothold in the strangeness, though he still doesn’t quite … 

“It’s just, Cas, you don’t look like a thing that has sex with people. You look like if you had people they’d be, like, window cleaners.” OK, that may in fact have gone the rude, undignified, and whiny route. It doesn’t get a rise out of Cas, though. The angel towers silent and impenetrable above him.

Sam watched a documentary, once, on window cleaners in New York. It hadn’t exactly covered window-cleaning related sexual practices, but Sam could improvise. He sees himself suspended in straps and harness, swinging on a thread umpteen stories up, burning in a blaze of sun and glass. Naked, jerking off, spattering sticky white on window glass. He’d be tiny against that vast expanse. Cleaning up afterward with some kind of squeegee. (No. Sam hastily edits that last bit out.) As a fantasy it’s, well, novel. The harness would chafe, pulled agonizingly tight under his arms. Sam could do something with that. He swallows, swallows again, feeling sweat prick and tickle on his chest and his erection straining uncomfortably against his jeans. He could do quite a lot with that. But there aren’t ropes or a harness or scaffolding or anything. And Cas is still shifting in front of his eyes. The mountain’s back, then a reef of coral, vast brain shapes and branching limbs studded with living shells and slimy weed. Then there’s a softly pocked metallic surface, a sense of old, old, old, old and infinite distance. Meteorite. Then back to the Chrysler. The only thing they have in common is _steep_. 

“You want me to climb?” says Sam. It’s the only thing he can think of.

Cas still doesn’t answer. His silence is tugging at Sam the way his bulk and mass do, at once quieting and prodding, challenge and relief and demand for surrender, coming and going in pulses. Sam’s over the need to abase himself now. That’s too quick and easy, not enough. This is a test. He wonders, instead, what it would be like to offer Cas the burn of muscle, slow, agonized pulls, hand over hand, the risk of shifting footholds. That feels right. 

He flexes his hands, gauging the ascent. He won’t make it to the top, he knows that. He doesn’t exactly want to. He’ll get as high as he can and then let gravity take him. Which might be a problem, depending on how literal this place is. Sometimes a fall off a skyscraper is just a fall off a skyscraper.

If worse comes to worse Cas can probably bring him back. Sam’s feelings about resurrections are mixed-to- _no-fucking-way_ , but he can’t very well ask Cas to show up at the Bunker with his smashed body and explain to Dean that Sam fell off him during sex. That wouldn’t go well. So, OK. Cas can bring him back. He sets his foot against Cas’s base and looks up.

“If I plummet to my death during orgasm, bring me back,” he says. “One time offer,” he adds. He doesn’t want Cas to take it as some kind of general _carte blanche_.

“You won’t fall,” says Cas. At least he’s quit with the strong, silent skyscraper routine.

“I’m safe with you?” says Sam. “Cause, dude, it really doesn’t look like it.” 

Not that he’s complaining. The thought of dangling up there with nothing but the strength of his grip between him and sheer shattering drop, that and the thought of the climax, the point when he won’t be able to hold on, those are going straight to his dick. It’s standing straight and proud, half in defiance of all this dwarfing phallic looming, half in anticipation of surrender. Sam’s not sure if he’s dizzy from the blood rushing south or from the imagined vertigo.

“You are not safe with me,” says Castiel. “This isn’t safe. But you won’t fall.”

 _What if I want to,_ Sam thinks. What if that’s the summit he’s making for? Isn’t that what it’s about for anyone else, deep down, under the whole “because it’s there” thing? You want to stand on the peak, yes, but then you also want to step over the edge. 

Still, that might not be exactly fair to Cas. It’s hard to see how Cas can get off on playing rock gym anyway, but Sam jumping ship mid-act could be, well, inconsiderate. Sam would like to think Cas agreed to this crazy experiment because he wants it, too. And he’d like to think he’s the kind of guy who takes that into account. There’s more than one challenge here.

He reaches up experimentally, spreading his palms, trying to feel like this is Cas. It’s a cliff-face right now, natural rock. Sam breathes the cool neuter scent, feels it scrape against his nipples through his shirts. The surface is immovable, rock-solid rock, but at some subliminal level Sam senses it accommodating him, shaping niches for his hands and ledges for his feet, preparing difficult overhangs and treacherous scree, impossible victories and defeats, a subtler excitement than any simple climb-and-drop. Sam’s breath catches. He closes his eyes and opens his lips against the rock, touches it with his tongue, tastes salt water and seaweed. Something, a fish, brushes past his knuckles. But his eyes open on the building, rectangular limestone blocks and a cornice just out of reach. He’ll have to jump for it.

“Should I, uh, undress?” he asks. He doesn’t much want to. Sam’s into pain, yes, but only in defined ways that don’t include full-body abrasion. Through all Cas’s kaleidoscopic changes, none of his surfaces look comfortable. 

“I think that would be unhelpful,” says Cas. 

Thank fucking God. Sam’s shirt’s a bit tight in the shoulders and short in the sleeves, not the best thing for climbing in, but it beats the alternative. He spits on his palms — gross, but, hey, it’s sex — and jumps for the cornice.

The world tilts instantly away from him. Wind sings in his ears. Rock vibrates faintly under his hands, a hum that grows stronger the higher Sam goes. He could almost be deep in the building, edging up an elevator shaft, if it weren’t for the awareness of utter exposure. He’s not inside. He’s a tiny, crawling thing and the sky is watching. 

Fuck that, Sam thinks. He may be a fly on a wall, but he’s not nothing. He’s the beat of his heart and the burn of his lungs, he’s sweat that hisses like acid on the rock. He’s the smear of blood where Cas’s edges are cutting his hands. The blood sinks in and the mountain quivers with a groan of boulders, gravel shifting loose and rattling into the abyss. Sam grits his teeth and goes on.

Sometimes when he looks up there are lights in windows, and Sam catches a glimpse of colossal art deco heads against the sky, man and lion, eagle and ox. The ox tosses its horns, the lion growls and the eagle screams, but the man looks down impassively, a fixed, monumental gaze. It turns Sam on like no lover’s look ever has. He has to stop and fight to keep his hand on its current window-ledge, to not reach for his dick and jerk off, right the fuck now, dirty and desperate. He knows it wouldn’t move that impartial face to the slightest flicker of interest. He’d just hang there, after, shamed and trembling in his sticky jeans, judged and found wanting. 

He doesn’t give in. He won’t want that, not yet. He hauls himself onto a narrow balcony with a silent scream of exertion and rests for a moment, cooling his hot face on the steel rails. He’s gotten high. He can’t see the ground.

Other times he’s climbing the mountain or scaling the underwater cliff, black fire in his lungs, currents plucking and stirring under his clothes, teasing his nipples and groin. He’s learned not to break his rhythm, but each shift of the scenery jolts through his balls, almost jostles him off the cliff-face, splits his lip against rock, trying to make him fall or go back or come. He bares his teeth savagely, wills his dick to wait, _wait!_ , and grabs the next ridge, closing his hand around its sharpest point and groaning at the warm, stopgap release of blood. There’s a spotlight stabbing the sky from the skyscraper’s roof. 

Once he touches worn, cool meteorite and feels a different jolt, awe and a quick warmth of memory, Dean taking him to the Museum of Natural History, in New York, when he was ten. _Look, Sammy, this one came from outer space._ It ought to be wrong, right now, off-putting, when he’s sobbing with the effort not to come in the midst of a metaphysical sex act, but it isn’t. It’s good. He leans his forehead on ancient space rock and lets whatever it is wash through him, grace, gratitude. Then he goes on. 

He’s lost in it now, his own weight working with him and against him, pulling him back and forcing him on like rough, strong hands, arousal dragging at his balance like a ball and chain. Sam’s usually been able to lift his partners, to throw his weight around, even with guys. Oh, from time to time he goes for reversal, has someone tie him up, gets hooked on someone’s blood. But that isn’t quite what he wants. He knows that now. _This_ is what he wants. His will pulling himself up, the hugeness that is Cas reeling him in. The gravity increases with his every move. An inexorable end waits ahead, squeezing his balls, kicking the base of his spine. _Boy_ , it says. Its voice is nothing like Jimmy’s now.

Sam inches up another foot or so, hands slipping and muscles screaming. The pressure against his erection is exquisitely painful. His face is scraped raw, mucky with blood and sweat. He can’t tell where he is anymore, building, sea-cliff, mountain, meteor, vertical or horizontal or sphere whistling through space. He can’t tell who he is. It shifts like Cas had shifted, Sam, nothing, something, nothing, Sam. This is it. He’s stopped climbing. He’s lying prostrate, as he’d wanted to at the beginning. He can’t feel anything but the blood that thuds in his ears and hammers his groin. _Please,_ he thinks, _please_. Nothing happens. Then he shapes the words with his lips against the rock and it hits. 

No, he won’t fall. Sam gets that now. He can’t. He’s spinning, pinned and melded to Cas, held by the law of gravity, by the gaze of the impartial face. It’s a weight he can’t resist. His mind is being crushed to nothing, dizzy and eager with assent. But his stick-figure body goes right on acting on its own, convulsed with frantic, ragged thrusts that break into wet warmth and the smell of come. The pleasure is so unexpected, so human that Sam sobs with release and relief. The hurtling pressure around him subsides, grows gentle. He’s lying without thinking, lapped in weight that cradles him, now, like warm, heavy water. 

After a time Sam lifts his head and looks around. It’s the underseascape, all right. The coral reef is a gentler slope, now, a living ecosystem. Clusters of bivalves root all around Sam, opening, closing, filtering currents of air? water? something else? something dense and nutritious. The whole scene is netted in quivering shocks of light. Everything is heavy with salt. Sam pulls himself into a half-sitting position— his limbs are still weak and trembly — and wonders. What is he supposed to do now? It’s over, isn’t it? How does he get back?

Except, Cas. Cas just gave him, gave him … well, that. Whatever that was. And Sam hasn’t done anything for him. So it isn’t over. Sam is supposed to do something in return, something reciprocal, thread his way through the strangeness and give Cas pleasure. And he wants to, wants to give back and bring Cas off. He just doesn’t know how. It’s not like he can jerk off a skyscraper, even when it’s not masquerading as coral reef. The Chrysler building’s a bit too damn phallic for handjobs.

Unless … after all, it’s not a skyscraper right now. That means something. Fuck phallic. Phallic is not the only way to go. Sam closes his eyes and breathes in, remembering. Amelia’s legs spread and dangling over his shoulders, his head between her thighs, her heels drumming his back, Jess’s exultant cries, salt slits opening to the searching touch of his tongue, the hot rush of wet, lips sore with sucking, his whole face dewed and sticky. Sam always loved going down on girls. 

He trails his fingers experimentally along the delicate edge of a shell. It fans open. Sam senses a stir along the reef, a rustling anticipation. There are more of the creatures by his face. He touches scalloped ridges with his tongue, kisses along closed seams. One of them eases open. He dips his tongue in, lapping, goes deep, touches something lithe and moving at the center. His mouth floods with salt. He’s the one who cries out, astonished intimacy striking deeper than orgasm. It ripples out, spreading, spreading through Cas, through the whole landscape, fields of shut, secretive lives opening, in unison, spilling white light. Angelic. Holy, holy, holy. The mountain under Sam grinds, trembles, and erupts in a mighty arc, a skyscraper’s worth of shattered glass.

Cas must have said something. 

Sam hangs on, panting, shielding his face in the crook of his elbow against flying shards. The flannel smells comfortingly of Dean. No wonder it doesn’t fit. It must be Dean’s. He’s wearing Dean’s shirt. The mountain? building? boulder? reef? sways and lurches around him. His grip is slippery with sweat or seawater. He wonders if, after all, he’s going to fall.

He doesn’t. The overload eases, like he’s being winched down in careful, undignified jerks. Helicopter rescue or something. Sight, or the simulacrum of seeing, comes back, and Sam’s body repositions itself. He’s sitting on a boulder next to Cas, Jimmy Novak Cas. They’re both fully clothed, not touching, and there’s no building, no mountain, no coral reef. The plain Sam had first arrived in is now a vast, subdued glitter streaked with dull greens and reds and browns. The gravel or grass or whatever it was has become dunes of broken glass, tangled in a wrack of damp seaweed. The air smells of ozone and the alkaline tang of the shore.

“You’re bleeding,” says Cas. He takes a white square of handkerchief from his pocket and presses it hard over Sam’s left eye. Sam’s a little surprised that that’s all that’s bleeding. He watches the frown lines by Cas’s mouth, inches away. Cas looks intent and ordinary.

“I can’t heal you here,” he says. “We’ll have to hope the excursion was worth a small scar.” 

Sam shrugs. “Did you . . . was it, I mean,” _was it good for you_ seems ludicrously inapt. It’s not that Sam’s insecure, exactly — in this context he’s fairly sure a miles-wide radius of seaweed and broken glass is a compliment — but he’d like to hear Cas’s end of things.

“It was fine,” says Cas.

That’s a little deflating. Cas usually means to be affirming when he says that stuff, but Sam notes for the future that it’s better not to ask. He should know not to go fishing for compliments in these particular waters. Miles-wide radius of seaweed and broken glass, he reminds himself. And it’s not like he couldn’t damn with faint praise, too, if he set his mind to it. No tentacles. 

He prods a bit of seaweed with his toe. There are things moving in it, he realizes, tiny crabs, a bright red anemone in a pool the size of Sam’s fist. Something scuttles over Cas’s shoe and Sam grabs for it, a strange bug shape and a tickle of limbs. Fucking hell.

“Look, Cas,” he says, “a trilobite. A fucking trilobite. These things have been extinct for, like, a hundred million years.” This one’s a few inches long, brown and glossy. It looks absurdly like its fossil, but it’s moving against Sam’s palm. He cups his other hand over it with infinite care.

Cas’s face breaks into a smile. 

“Two hundred and fifty million,” he corrects. “Give or take. I’ve missed them.” He takes it delicately from Sam and peers at it. “Hello,” he says. Then he bends down and lets it go. It scuttles off behind a pile of glass. Cas turns his smile on Sam.

“Thank you,” he says. He puts his hand over Sam’s. It’s a bizarrely human gesture. Sam keeps his hand still, as though he were still holding the trilobite.

“Dude,” he says, “it’s your trilobite. Trilobites aren’t part of my sexual repertoire.” 

In fact, if all this, like, exploded from Cas at the climactic moment, does that make it jizz? Sam pulls his feet back hastily. Is Cas thanking him for a trilobite jizz orgasm? Sam _definitely_ shouldn’t go fishing for compliments from him, not ever again. Ever. Still, there’s warmth in the way Cas is looking at him, with a trace of wonder in his expression. It’s not wonder at Sam, but it’s something Sam was a part of. It makes him shy, but it also settles something. Sam can ask his question now, though he thinks it’s already been answered.

“I’m not human, am I?” he says. “Not a hundred percent. I mean, this,” he waves his hand at the wasteland of glass and kelp, at the whole certified X-File porno thing, “doing this isn’t human.”

Sam isn’t going for melodrama. He’s over that. He’s not asking for purifying, he won’t say Yes again, he won’t take the one step, the one swallow, that makes him a monster. He’ll be what he is. And Cas wouldn’t be here if he still thought Sam was an abomination. Well, maybe he would. Cas might kink on abomination sex. But it would have been different.

Cas sighs. “No,” he says. His voice is gentle, but there’s nothing gentle about his eyes. “If you were purely human you couldn’t breathe in this place. You wouldn’t be able to stand. You would have been twitching on the ground the moment I brought you here. And I’m not certain I could have got you back. I told you it wasn’t safe.”

“You told me that _after_ I didn’t twitch and die,” Sam points out. He’s not really angry. It would have been Cas’s problem, after all. Hadn’t Cas run through the showing up on Dean’s doorstep with Sam’s mangled sex-accident corpse scenario for himself? He never did have much sense of self-preservation.

“Yes,” Cas agrees. “Though the rest could have destroyed you as well. No, you aren’t quite human. Any more than I am wholly an angel.”

Sam opens his mouth to say that Cas seems pretty fucking angelic to him. Then he shuts it. He has no real way of knowing what Cas is missing, how he’s changed, what he might have lost and won’t get back. Souls, Leviathan, purgatory, grace taken out and put back, Naomi fucking with his mind. Cas may be on the shortlist of beings Sam doesn’t get to complain to. He looks at the familiar serene wryness in Cas’s human face, at the trenchcoat, a little rumpled, at Jimmy’s tie, badly knotted and askew. No, not Jimmy’s tie. Something’s changed.

“You have a new tie,” Sam says.

“Yes,” says Cas. “I saw it in a store a little while ago. I liked it, so I bought it. I did pay.”

“Bees,” says Sam, “nice.” They’re embroidered in gold silk on navy, grouped around tiny, ridged hives. It really is a nice tie.

“I like bees,” says Cas.

Sam tries to sort through, to remember. It’s there, somewhere, a point in the arduous climb. A white field, clover, slippery grass wound cuttingly in his fingers, a dull taste of crushed honey, heat on the back of his neck and an ambient hum. Easy to miss in all that drama, what with the bivalve stuff and the meteorite and the Chrysler building. It hadn’t even registered at the time. But now, out of all of it, it’s that buzzing warmth that lingers, tickling Sam’s groin, flooding him with expansive wellbeing. He feels almost Cas-sized. Or maybe something less soaring, more spread out.

He reaches over to straighten the bee tie. Then he tugs it till Cas tilts towards him and they’re kissing.


End file.
